Science of War (and Peace)

Science of War (and Peace) Prof. Lynn R. Cominsky Department of Physics & Astronomy

Talk Outline • Different sides of science • Atoms for War • A bit of history • Fission • Fusion • Effects • Atoms for Peace • Enrichment • Proliferation • Current state of affairs with Iran

Science – it’s not good or bad • “The good thing about science is that it's true whether or not you believe in it.” -- Neil deGrasse Tyson • “ When you see something that is technically sweet, you go ahead and do it and you argue about what to do about it only after you have had your technical success. That is the way it was with the atomic bomb.” -- J. Robert Oppenheimer

Science does not discriminate

Atoms for War – some history • World War II coincided with advances by physicists in understanding the inner workings of the atom • These physicists understood that it was possible to release huge amounts of energy by breaking apart or smashing together nuclei of atoms – far more than can be released in chemical reactions, which rely on electrons

WWED? • By 1939 many prominent (mostly Jewish) physicists had fled Europe and resettled in the USA • Albert Einstein signed a letter to President Roosevelt alerting him to the terrible potential of weaponizing nuclear reactions • But until Pearl Harbor in 1941, the USA did not invest much in this research

Manhattan Project • After 1941, the US began to race Nazi Germany to develop nuclear weapons • Manhattan Project was really located in Los Alamos, NM • Most of the funding went to build factories that could produce the materials needed to make the bombs • The first successful test was Trinity on 7/16/45 in Alamogordo, NM

p p n n e e Nuclear physics vs. Chemistry • Chemistry: change the number of electrons  typical energies involved are a few electron Volts (eV) • Nuclear physics: change the number of protons or neutrons in the nucleus  typical energies involved are millions of eV 4He Helium Atom: 2 electrons (e) 2 protons (p) 2 neutrons (n)

Isotopes of Uranium • 235U is ~0.7% in nature but is the major ingredient in chain reactions. 143 neutrons. • Uranium: 238U is >99% in nature. Uranium has 92 protons, and 238U has 146 neutrons. 10 g of 238U

n n n n Fission Weapons • Fission • releases energy in elements heavier than Iron • Bombard U or Pu with neutrons, they split into fragments, releasing energy • “A” bombs 235U

The first “A” bombs • Trinity – Gadget (7/16/45) • Alamagordo test range in New Mexico • 20 kTon yield • Little Boy (8/6/45) • Hiroshima • 15 kTon yield • Fat Man (8/9/45) • Nagasaki • 20 kTon yield Museum display in NM

How to make an “A” bomb • Use >90% 235U • Squeeze and confine evenly • Reflect neutrons back into 235U • Use initial explosive device to trigger Little Boy (Hiroshima 8/6/45) 3 m A-bomb dome http://www.pcf.city.hiroshima.jp/peacesite/English/Stage1/1-3/1-3-3E.html

“Fat Man” style of A-bomb • High explosives are arranged to form an imploding shock wave which compresses the fissile material to supercriticality. • Burst of neutrons from generator is timed for moment of maximum compression

D D Fusion Weapons • Fusion • Elements lighter than Iron release energy when combined • Deuterium, Tritium, Lithium • Reactions that occur inside Sun • “H” bombs • Thermonuclear Reactions • Heat from reaction increases reaction rate, so less fuel is needed  “efficient” bomb 4He

Why is an atomic bomb so much worse than a TNT bomb? • Amount of heat and light energy released is 1000 times greater • Explosion is accompanied by invisible, penetrating and harmful radiation • After explosion, radioactive fallout remains and continues to damage living things for days  weeks  years Ground level view of Hiroshima cloud

Physical Effects of Nuclear Weapons • Thermal • Fireball  Firestorms • Mushroom Cloud • Initial (prompt) Radiation • Alpha particles (4He++) • Beta particles (e+ and e-) • Gamma-rays (g) • Neutrons (n) Trinity Bridge in Hiroshima

Hiroshima buildings Physical Effects of Nuclear Weapons • Pressure Blast Wave • Buildings collapse • Fallout • Radioactive fragments which stick to air particles or dirt that is sucked up mushroom stem • 80% falls back down in first day • 90% falls back down in first week • 10% lasts weeks  years Google Nuclear Weapon Effects Calculator to try it out on your city! Nagasaki victim

Physical Effects of Nuclear Weapons • Electromagnetic Pulse • Strongest for very high bursts • g-rays ionize air  electrons • Electrons create large currents in air • Currents are picked up by power lines • Power surges shut down grid, destroy attached electrical devices • 1.4 Mton airburst in 1962 knocked out lights in Hawaii over 1000 miles away

Electromagnetic Pulse Effects http://www.fas.org/nuke/intro/nuke/emp.htm

Nuclear Weapons are Scary! • Most of the lasting effects are due to radiation, so are odorless and colorless • Genetic damage and cancers can take 20 or more years to develop • A single bomb can kill 100,000 people and destroy an entire city • It does not take much nuclear material to create a big explosion • However, it does take considerable engineering to make a bomb that works

How big are the weapons? • 1 kTon = 1000 tons = 2,000,000 pounds of TNT equivalent • ~2 pounds of 235U  20 kTons • Today’s warhead is 100-200 kTons • Largest underground burst: 4.5Mtons • Largest airburst: 58 Mtons • Over 1700 known tests since 1945

Atoms for Peace • After the horrors of Hiroshima and Nagasaki, Eisenhower launched ‘Atoms for Peace’ in 1953 • The goal was to “solve the fearful atomic dilemma… to find the way by which the miraculous inventiveness of man shall not be dedicated to his death, but consecrated to his life.” • This program built the first nuclear reactors in other countries including Iran

Uranium processing • Uranium is mined as ore from open pits or deep shaft mines, often with the help of extracting solutions • At nearby mills, ore is crushed and U is extracted, leaving behind radioactive tailings • Extracted U is then leached (with sulfuric acid) forming a concentrate known as “yellowcake” (aka Uranium oxide U3O8) • Yellowcake is then turned into UF6gas, which can be cooled to a solid for easier transport

Enriching Uranium • Naturally occurring Uranium must be enriched to >90% 235U in order to make fission weapons (or to ~5% for nuclear power plants) (called HEU) • Enrichment methods • Gas centrifuge (now being used in Iran and found in Iraq after 1st Gulf War) • Gaseous diffusion (used in USA) • Electromagnetic isotope separation – (unexpectedly found in Iraq after 1st Gulf War)

Gas centrifuge • Uses successive stages to isolate isotopes by weight – lighter mixture is sent on to the next stage, heavier mixture is sent back to the previous stage • Requires thousands of successive stages to create weapons grade 235U

Enriching Uranium in Iran • Iran has developed an extensive, underground enrichment facility for Uranium at Natanz • Most of the centrifuges are underground, in order to withstand aerial attack – only 1-2% would be needed to make sufficient quantities of highly enriched U for a weapons program • Iran’s stated goal for this facility is production of sufficient low-enriched U (LEU) to generate 6000 MW electricity through power plants

Ahmadinejad visits Natanz 4/08 • Inspecting the new IR-2 centrifuges

Nuclear Non-Proliferation Treaty • Vertical – development of new weapons by the “Big 5” • Horizontal – spread of weapons to other countries • “Haves” agree not to spread weapons, materials or technology to “have-nots” – also, to stop vertical proliferation • “Have-nots” agree not to try to acquire weapons from the “haves,” and will accept inspection and regulation of “peaceful” nuclear technology by IAEA- this stops horizontal proliferation

March 2015 Non-proliferation Treaty Map • File:NPT Participation.svg: Allstar86, L.tak, Danlaycock

Nuclear Non-Proliferation Treaty • NPT indefinitely extended since May 1995, confirmed again in 2000, reviewed most recently in May 2010 • Now signed by 191 countries • N. Korea ratified in 1985 then withdrew in 2003. In 2006 and 2009, it conducted nuclear tests. • Israel, India and Pakistan are still not signatories. • Iran remains a signatory but has been in violation for many years now. It did not sign the “Additional Protocol” in 1997 which called for reporting additional information and unannounced inspections by IAEA • In 2002, Iranian dissidents announced the existence of 2 facilities that were not publicly known: Natanz and Arak • As part of the new treaty, Iran will sign and obey the Additional Protocol rules

New treaty with Iran – good? • Treaty negotiated by Iran, Britain, China, France, Russia, Germany, the US and the EU • limits installed enrichment capacity • limits enriched uranium stockpiles • restricts uranium enrichment activities to one site • redesigns the Arak reactor to make it less suitable for producing plutonium for weapons purposes • Iran will not reprocess its spent fuel to separate out plutonium for 15 years and has declared intent to stop reprocessing entirely

Iran treaty – verifiable? • Lengthens the “breakout time” to convert nuclear materials from peaceful to weapons use: • Iran to disassemble and store 13,000 centrifuges out of 19,000 – leaving only 5000 old ones at Natanz + 1000 at Fordow to be used for research • Iran to reduce stockpile of LEU from 10,000 to 300 kg • Iran to replace reactor core at Arak with different design that will take 15 y to produce enough plutonium for 1 weapon (rather than current design of 1 year) • IAEA will monitor all mining and importing of uranium ore • http://blog.ucsusa.org/iran-nuclear-deal-830

Some hopeful signs • New START (STrategic Arms Reduction Treaty) signed April 8, 2010 by Obama and Medvedev – and then ratified by Senate and put into force on Feb. 5, 2011 • Limits deployed strategic nuclear warheads to 1,550 • Limits deployed and non-deployed ICBM, SLBM, and heavy bombers to 800. • Limits deployed ICBMs, deployed SLBMs, and deployed heavy bombers to 700 • For the first time in a long time, US and Russia are slowing vertical proliferation

More hopeful signs • 2014 Nuclear Security Summit in the Hague, the Netherlands (3/26-27/14) • Concrete agreements between 58 world leaders to prevent terrorists from acquiring nuclear materials that could be used for weapons (HEU and Plutonium) • New agreement to improve security of radioactive material that could be used for “dirty bombs” • Improvements in the exchange of information and international cooperation • This is the third bi-annual summit

Words of wisdom? • “To be prepared for war is one of the most effective means of preserving peace.” -George Washington • “Peace cannot be kept by force; it can only be achieved by understanding.” - Albert Einstein

Additional Resources • Carnegie Endowment for International Peacehttp://www.ceip.org/ • To Kill a Centrifuge http://www.langner.com/en/wp-content/uploads/2013/11/To-kill-a-centrifuge.pdf • Federation of American Scientists http://www.fas.org • Verification report about Iran http://fas.org/pub-reports/verification-requirements-nuclear-agreement-iran/ • Iran Watch (Wisconsin Project) http://www.iranwatch.org/ • Union of Concerned Scientists http://ucsusa.org • Nuclear Security Summit 2014 http://www.nss2014.com/en

To Kill a Centrifuge • In 2010, news reports indicated a new type of malware had been uncovered. (An older, less effective version was later discovered dating back to 2007) • “Stuxnet” penetrated Windows computers, then took aim at specific programmable logic controllers made by Siemens and resident in Iranian enrichment centrifuge systems that were IR-1 models • Reports indicate that up to 10% of Iranian centrifuges (~1000) were destroyed by varying the rotational speeds while playing back a loop that indicated normal operations were occurring

From Langner’s report • “Stuxnet will not be remembered as a significant blow against the Iranian nuclear program. It will be remembered as the opening act of cyber warfare” • “Stuxnet started as nuclear counter-proliferation and ended up opening the door to proliferation that is much more difficult to control: The proliferation of cyber weapon technology.”

Science of War (and Peace)